Hydraulic coupling for internal-combustion engines with exhaust gas turbines



Jan. 18, 1955 WARNER 2,699,643

I HYDRAULIC COUPLING FOR INTERNAL-COMBUSTION ENGINES WITH EXHAUST GAS TURBINES Filed March 31, 1949 l v I/ III// /////1 INVENTOR United States PatentO HYDRAULIC COUPLING FOR INTERNAL-COM- BUSTION ENGINES WITH EXHAUST GAS TURBINES Douglas K. Warner, Sarasota, Fla. Application March 31, 1949, Serial No. 84,677

3 Claims. (Cl. 60-13) This invention relates to hydraulic couplings, more particularly to couplings utilizing fluid inertia as opposed to friction drive.

The invention improves the efliciency and capacity of such a drive by placing on the hyraulic drive only a small part of the power being delivered.

One of the utilities of such a device is' to connect an exhaust-gas-blowdown turbine to an engine shaft in a manner to give high efliciency and yet allow a very slight amount of slippage so that the turbine blades turn a trifle faster than the engines crankshaft so that the exhaust heat may be evenly distributed in all the blades as is also the cooling effect of waste heat steam jets expanded in the hollow walls of the exhaust nozzles during the half cycle that exhaust is not flowing.

In the drawings:

Fig. 1 is a side cross sectional view through EE, Fig. 2, of a turbine and its coupling of full scale dimensions showing one of the cylinders of a radial engine exhausting to the turbine while steam from the cylinder head is being deflected to turbine inside the baflle wall.

Fig. 2A is a section through Fig. 1 at AA.

Fig. 2B is a section thru BB of Fig. 1.

Fig. 2C is a rear end View of coupling.

Fig. 3 is a front end view of inner coupling portion and the lower half of outer portion of coupling as seen at DD, Fig. 1, looking to the right from the crankcase, and Fig. 4 a top View of same.

Fig. 5 is an inside sectional view of the outer part of the coupling cut in two and is the hub of the turbine shown sectioned at AA, Fig. 1.

Fig. 1 shows a cylinder 50 and a short stroke piston 51 above whichan air-fuel mixture rushes in through inlet ports 54 pushing the burnt gases across the cylinder and out exhaust ports 56 and onto the blades 41 of the first stage of the three-stage blowdown turbine with rotors 44, 43 and 42. Wet steam entering passage 53 in cylinder head 52 moves through the head evaporating the water and enters the hollow walls 48 of exhaust ports 56 and is directed into blades 41 by baflle 49 flowing only when the hot gas pressure has been cut off by piston closure of ports 56. Steam at about 300 and hot gas at 2800 flow alternately through moving blades 41, 47 and 46 and intervening stationary reversing buckets 40 and 39 which are mounted in cylinder head extensions 32.

The bore of the turbine hub has helically cut grooves 3 with points 4 projecting in the direction of turbine rotation. The inner portion of coupling 5, Figs. 3, 4 and 5, has much deeper grooves 6 cut helically opposite to the twist of grooves 3 and has points 7 inclined opposite to the direction of rotation, when the coupling is in normal operation and in the same direction as that of rotitign when the turbine first attempts to turn the engine s a t.

Oil fed to the coupling throughdrilled hole 8 in engine crankcase 9 the rear bearing extension of which 9A rotatably mounts said coupling and this oil now passing through another hole 8A is caught by the edge 4 of groove 3 in the turbine hub 2 and is thrown forwardly adjacent surface 10 to the groove 6 in the inner member of the coupling. Here the oil is slowed down and reversed back to be caught by other edges 4 in hub 2. Each time the oil is thrown from one portion to the other it is also thrown rearwardly, due to the grooves being cut spirally, and the coupling thereby becomes an oil pump.

The oil slows down in the large grooves 5 of the inner member 1 first because it always moves at slower R. P. M.

2,699,643 Patented Jan. 18, 1955 and second because these grooves are much nearer the shaft center and so move at much lower speed. Slowing the oil down in this dilfuser type manner increases the 011 pressure against the forward portion of groove 5 so 6 tending to push it along with the turbine hub and the inertia energy of the oil is reversed giving the groove 5 a reaction force in the direction of turbine motion.

At the rear of inner portion 5 is a fllange 11 drilled with 12 evenly spaced holes 13 fitted with bushings 14. The tmy aluminum alloy pinions 15 shown here with 12 teeth and 7 P. D. are formed on shafts 16 which extend through bushings 14 and are splined on the oppos1te ends to receive the slightly larger /2 P. D. light metal 12 teeth pinion-gears 17 and, after mountmg, the gears are upset to hold them in location.

A large gear 18 here shown as 3" P. D. is cut on the end of the turbine hub to mesh with the twelve pinions of /2" P. D. the large gear having 72 teeth and the pinions 12 teeth.

Another gear 19 with 84 teeth and 3.125" P. D. meshes with the smaller pinions and its hub 20 is splined ito fit inside the end of the crankshaft 21 and drive the atter.

One eighth of the pressure on the teeth of gear 19 comes from the coupling while Ms thus comes directly from the much higher leverage of the turbine hub pressure on the teeth of pinions 17 if we assume the bushings are frictionless.

With the turbine and shaft turning at high speed the centrifugal force on the pinions and their shafts place considerable load on the bearings which tends to retard their rotation in the bushings by adding friction and in so doing the effective leverage is increased so that the coupling may now take only 5% of the load being transmitted and if the eificiency of the hydraulic coupling is the efficiency of the drive becomes 99 /2% and the power lost /z% of total) goes into pumping lubricating oil through the engine to keep it cool.

Oil from the grooves 3 and 5 passes through holes 22 in flange 11 under an original high pressure increased by the pumping effect of the coupling and passes inwardly between flange 11 and gear 19 in space 23 and thence forwardly through hub 20 in holes 24 and through matching holes 25 in locking plate 26 and on through the crankshaft to the engine bearings.

When the turbine is first started by jets of stored CO2 (not shown), the inner portion of the coupling is compelled to turn in the opposite direction. as the pinions race around the fixed rear gear 19 which has less leverage on the pinions than the gear on the turbine hub. This causes oil to be pumped furiously into the engine increasing its temperature and the bearing temperatures and so greatly decreasing the breakaway torque so that the engine quickly starts. Then the inner part of the coupling changes its rotation direction and follows the turbine hub at say 90% of the turbines speed. Thus if the turbine speed is 36,000 R. P. M. the coupling hub turns at 34,600 and the engine at 35,820 R. P. M. and the turbine blades get cooled 3 times a second.

To prevent too much oil from flowing out to the pinions 15 and 17 and their shafts 16, labyrinths 27 and 28 are cut on both faces of the flange 11 and on the tur' bine hub rear end and forward face of gear 19. Holes in the top labyrinth grooves carry the oil which leaks by the clearance to the bearings and the gears. The surplus oil is carried off in pipe 29 by the gas pressure from pipe 30 which balances turbine.

The gases which create the balancing pressure on the rear of the turbine are thrown into opening 31, drilled in one or more of the cylinder head extensions 32, by the first stage turbine blades. This gas has approximately the same pressure as the gases on the forward side of the turbine and thus minimize the rubbing friction of the rear of the rotor hub on the flange of the inner race of the coupling and in turn the rubbing friction of that flange on the face of the rear gear. The rear gear is fastened to the crankshaft by bolt 34 extending through the center of hub 20 and screwed into plate 26 which is itself screwed and locked by jamming within the bored hole in the rear of the crankshaft.

The rubbing of these parts against each other is balanced by the oil pressure of the oil trying to swirl out between them. To prevent the turbine from moving forward the thrust bearing 35 is provided, and oil passing this bearing is blown through pipe 36 into the engine crankcase by the high. surrounding gas pressure, a shield 37 being provided'to catch the. oil as it .is' thrown out from the' bearing; As described in application Ser. No. 67,443' filed- Dec; 27, 1948, now abandoned, the crankshaft counterweight acts asa centrifugal pump'to throw the oil outto a double pipeboiler feed water heater '(not shown) and the gases. which go out with that oil are" released at a pressure high enough: toinsure proper return of the cooled oil to the hydraulic coupling through pipe 38;' g

There are of course many-o'therutilitiesfor a non-wearing hydraulic coupling with very little slippage after attaining operating conditions and it is not intended that this application cover only the engine application shown.

The novelty centers on the use of particularly shaped buckets cut within the 'hub of a power generating source whereby the more rapid motion of this hub'than the metion of oppositely cutbuckets on a cone within it throws oil. into said cone buckets forcing. the latter toturn With it and finally the superimposing of a gearleverage to relieve-the'buckets ofmost' of'the' load so that the cou-- pling may be very small and light in weight.

What I claim is:

1. In an hydraulic transmission. an inner sleeve mem ber containing deep-bucket shaped grooves spirally, helically formed in its'outer surface terminating in sharp points tangentially directed and'an outer. member closely surrounding said inner member having helically formed shallow buckets'interiorly with opposite twist and also terminating in sharp points directed oppositely to the said deep buckets in said inner sleeve, means to introduce oil at one end of said grooves and means for withdrawing oil at the opposite end when said members are turning at difierent speeds.

on said shafts on each side of said flange near the outerrim thereof, a spur gear on the corresponding end of said outer member meshing with the pinions on one side of said flange and a spur gear attached to a shaft concentric with said transmission meshing with said pinions on the opposite side of said' flange said pinions and gears varying in pitch diameter on opposite sides of said flange whereby part of the torque in said outer member is transmitted to said shaft through said hydraulic coupling and part through said gears.

3. The transmission of claim 1 incombination with a compound radial blowdown engine having turbine blades immediately adjacent said engine exhaust ports in said engine jetting hot gases on said blades when said ports are piston opened and jetting steam when said ports are closed; said transmission" coupling said engine to" said turbine blades whereby" said blades turn at different revolution speeds from said engineand thereby keep all blades evenly cooled by' steam.

References Cited in the file of this patent UNITED STATES PATENTS 1,473,487 McCarthy Nov. 6, 1923 1,831,690 Taylor Nov. 10, 1931 1,918,163 Wohlenh'aus July 11, 1933 2,007,032 Wach July 2, 1935 2,400,186 Armentrout May 14, 1946 2,511,135 Torrance June 13, 1950 2,602,296 Leahy' July 8, 1952 FOREIGN PATENTS 7 732,945 Germany Feb. 11, 1943 206,845 GreatBritain" Feb. 21, 1924 

